Guardian: Prince Charles will join at least 65 world leaders in Copenhagen later this month, it was announced today. In an unexpected move by Denmark, the prince has been invited by the host country to address the UN summit during the opening ceremony of the second “high-level” week of the conference, when political leaders arrive. But the Prince of Wales, who will only be in the Danish capital city for four hours on 15 December, will not take part in any formal negotiations. It is …